Diabetes Insipidus and SIADH PDF

Diabetes Insipidus (DI) and Syndrome of Inappropriate Anti-Diuretic Hormone (SIADH) Jessica A. Peters DNP, MS, RN, ACNP-BC Overview of DI and SIADH Overview of Diabetes Insipidus (DI) and SIADH ► Posterior pituitary gland produces two hormones arginine vasopressin (AVP) also known a...

Diabetes Insipidus (DI) and Syndrome of Inappropriate Anti-Diuretic Hormone (SIADH) Jessica A. Peters DNP, MS, RN, ACNP-BC Overview of DI and SIADH Overview of Diabetes Insipidus (DI) and SIADH ► Posterior pituitary gland produces two hormones arginine vasopressin (AVP) also known as antidiuretic hormone (ADH) and oxytocin AVP acts on the renal tubules to induce water retention, leading to concentration of the urine ► Clinical syndromes may result from deficiency or excess of AVP ► Central DI insufficient AVP is released in response to physiologic stimuli Can be acquired (head trauma, neoplastic or inflammatory conditions affecting the hypothalamus/posterior pituitary), congenital, or genetic disorders, but almost half of cases are idiopathic 3 Epidemiology ► Diabetes Insipidus Relatively uncommon in the United States incidence 3 in 100,000 cases Prevalence equal male and female nor is there variable occurrence in minority populations ► SIADH Incidence increases with age Prevalence variable and 2.5%-30% Hospital acquired or aggravated by the hospitalization – Arise postoperatively from stress, pain, and medications use 4 Definition- Diabetes Insipidus ► Central diabetes insipidus Head injury, either surgical or traumatic, in the region of the pituitary or hypothalamus may cause central Congentinal: wolfram syndrome ► Nephrogenic diabetes insipidus Chronic renal failure may impair urinary concentrating ability Pharmacologic – Lithium and demeclocycline 5 Definition- SIADH ► Serum sodium and osmolarity is determined partially by vasopressin-mediated distal renal tubular water retention ► Often occurs as a secondary syndrome in acute care Neoplasms, medications stroke, ARDS among others can all potentiate ► Clinical manifestations of SIADH are in part determined by the nature and course of any underlying disorder (CNS or pulmonary disease) Severity of hyponatremia, and by the rapidity with which hyponatremia develops 6 Causes of SIADH Hammer G., & McPhee S.(Eds.),. (2019). Disorders of the hypothalamus & pituitary gland. Pathophysiology of Disease: An Introduction to Clinical Medicine. Retrieved from: https://accessmedicine.mhmedical.com/content.aspx?bookid=2468&sectionid=198223896 7 Comparison Pathophysiology by Lack of Vasopressin: Excess Vasopressin: System Diabetes Insipidus SIADH Diabetes Dilute with increased Concentrated with Insipidus and Urine volume—polyuria decreased or normal volume SIADH Increased and Not decreased and not Thirst protective—normal protective—polydipsia intake Decreased— Tendency to Serum sodium hyponatremia due to hypernatremia water retention Increased by water Initial plasma volume Decreased by polyuria retention Dilute urine (